That should be the last plugin schema updates from me for now. As said on the streamlink Gitter channel, there are a couple of validation schemas left that could be refined according to the newly added stuff, but there are some problems.

$ GIT_PAGER=cat git grep -Pn --heading \
  -e 'validate\.any\(\s*None,\s*validate\.all\(' \
  -e 'validate\.transform\(\s*.+?\.search\s*\)' \
  -e 'validate\.validate\(' \
  -e 're\.Match,' \
  -e ',\s+validate\.Schema\(' \
  src/streamlink/plugins/

src/streamlink/plugins/ard_mediathek.py
75:                validate.any(None, validate.all(
81:                        "show": validate.any(None, validate.all(
src/streamlink/plugins/common_jwplayer.py
12:    validate.transform(_playlist_re.search),
src/streamlink/plugins/rtbf.py
59:        validate.transform(_video_stream_data_re.search),
src/streamlink/plugins/schoolism.py
31:        validate.transform(playlist_re.search),
src/streamlink/plugins/vimeo.py
30:        validate.transform(_config_url_re.search),
59:        validate.transform(_config_re.search),
60:        validate.any(None, validate.Schema(validate.get(1), _config_schema)),

common_jwplayer

That can be removed. It's not used by any plugin, and if 3rd party plugins import from that module, then they can re-implement it.

vimeo

There's already a PR for that plugin.

rtbf

I have local changes for that, but I don't want to submit a PR, as I can't test it. The site requires a registration with a Belgian address. The current implementation is most likely broken.

schoolism

I've got local changes for that plugin as well, but I haven't tested it yet, as it requires having an account. Maybe I'll take a look at this later, but not now.

ard_mediathek

Forgot to stage some changes after stashing and rebasing all the plugin changes a couple of times. Won't open another PR for that.

And then there are tons of other plugins with bad validation schema definitions and bad code styles. Fixing and updating those was not the plan in my recent changes.